扁蓿豆冷诱导基因差异表达分析

以直立型扁蓿豆幼苗为试验材料,采用cDNA-AFLP技术分析扁蓿豆在低温胁迫诱导下的基因表达差异.结果显示,利用筛选的64对引物组合,对0℃低温处理3～5叶期扁蓿豆幼苗的叶片cDNA进行扩增,共获得549条差异表达的转录衍生片段(TDFs).选取上调表达较好的43条片段进行克隆、测序、Blastx比对和功能分析,其中32个TDFs的蛋白序列与基础代谢、信号转导、转录因子、防御等功能有关,11个TDFs为假设蛋白、未知蛋白或没有找到一致序列.利用荧光定量PCR对3种不同上调表达差异片段进行验证,结果可从数值上更准确地显示差异片段在低温胁迫过程中的相对表达量.

cDNA-AFLP Analysis of Cold-induced Genes in Medicago ruthenica

In this test,common wheat root tips were treated with hypoxia water to explore the effects of hypoxia on nucleolar structure and function of root-tip meristematic cells of common wheat using serials of techniques,such as conventional cell preparation,silver staining,electron microscopic observation,indirect immunofluorescence staining and RT-PCR analysis.It was observed that,after hypoxia water treatment,(1)the nucleoli in the meristematic cells became swell,protruded and agglutinated;some inner vesicular and abnormal nucleolar channels appeared;the fine structures of the nucleolus were disappeared and even more,the nucleolus was segregated,etc.(2)Nucleophosmin B23 shuttled from nucleoli to nucleoplasm,even to cytoplasm revealed by indirect immunofluorescence staining techniques.(3)RT-PCR analysis indicted that the expression level of rRNA gene was lower obviously than that of control and the expression signal of C23 was undetectable.It means that the expressions of both ribosomal RNA and C23 genes were down-regulated significantly.Our results demonstrate that hypoxia treatment can not only damage nucleolar structure but inhibit its function.